Stairs along bezier path
Here's an approach which you may be able to vary according to your needs.


I'm assuming you would like the steps to be of equal depth .. so first, scale your curve to 0 in Z.
Ensure the Preview U setting on the curve, times the number of segments in the curve, is twice the number of steps you will need
In Object Mode, Alt C convert the curve to a mesh, and use the Loop Tools add-on > Space to space the vertices evenly along the mesh.





With Proportional Editing switched on to 'Connected' and 'Linear' move the topmost vertex back up to where it belongs. Set the radius of the proportional Edit large enough just to see some movement in the bottom-most vertex. As soon as the Z-dimension is significantly greater than 0, you can switch off proportional, and adjust by scaling/moving all in Z.
Use Select > Checker Deselect to select every other vertex, (Ctrl I invert the selection if necessary, to make the bottom vertex unselected.)





G G slide the selected vertices down their edges, until they meet the vertex below. (Do not have Automatic Merge switched on)
With Snap set to 'Vertex' and 'Active', with the existing selection, make a convenient vertex active, and (G Z) move it vertically until it snaps in Z to the vertex above it. 





In the N sidebar of the 3D view > Mesh Display, show edge length, and take a note of the depth of your steps
Assign an Array Modifier, with Constant Z Offset of that length, and the Count set to more than the number of steps - 'Merge' switched on.
With all doubles removed, F fill the faces.





Select all the faces, and AltE > Extrude by Vertex Normals
As you can see, because of the boundary effect on vertex normals, the top layer of steps is wonky. I've tried a ton of things to get round this-if anyone can make a suggestion I'd really appreciate it -
So it's necessary to GG slide down the top  layer onto the one below twice, CtrlV > R removing doubles as you go, and X dissolving the surplus diagonal edge.





But in the end, you get this.




I'm really hoping someone will come along and improve this.